// A general toy class
abstract class Toy
{
    public abstract void Play();
}

// Specific types of toys
class Car : Toy
{
    public override void Play()
    {
        Console.WriteLine("Vroom! I'm a car.");
    }
}

class Doll : Toy
{
    public override void Play()
    {
        Console.WriteLine("Hi! I'm a doll.");
    }
}

// The factory method
abstract class ToyFactory
{
    public abstract Toy CreateToy();
}

class CarFactory : ToyFactory
{
    public override Toy CreateToy()
    {
        return new Car();
    }
}

class DollFactory : ToyFactory
{
    public override Toy CreateToy()
    {
        return new Doll();
    }
}

// Using the factory method
class Program
{
    static void Main(string[] args)
    {
        ToyFactory carFactory = new CarFactory();
        Toy car = carFactory.CreateToy();
        car.Play();  // Output: Vroom! I'm a car.

        ToyFactory dollFactory = new DollFactory();
        Toy doll = dollFactory.CreateToy();
        doll.Play();  // Output: Hi! I'm a doll.
    }
}

// A general toy class
abstract class Toy
{
    public abstract void Play();
}

// Specific types of toys
class Car : Toy
{
    public override void Play()
    {
        Console.WriteLine("Vroom! I'm a car.");
    }
}

class Doll : Toy
{
    public override void Play()
    {
        Console.WriteLine("Hi! I'm a doll.");
    }
}

// The factory method
abstract class ToyFactory
{
    public abstract Toy CreateToy();
}

class CarFactory : ToyFactory
{
    public override Toy CreateToy()
    {
        return new Car();
    }
}

class DollFactory : ToyFactory
{
    public override Toy CreateToy()
    {
        return new Doll();
    }
}

// Using the factory method
class Program
{
    static void Main(string[] args)
    {
        ToyFactory carFactory = new CarFactory();
        Toy car = carFactory.CreateToy();
        car.Play();  // Output: Vroom! I'm a car.

        ToyFactory dollFactory = new DollFactory();
        Toy doll = dollFactory.CreateToy();
        doll.Play();  // Output: Hi! I'm a doll.
    }
}